Devulcanizing-bath.



UNITED STATES PATENT OFFICE.

JOHN MURPHY, OF NEW YORK, N. Y ASSIGNOR TO A'MADEE SPADONE, OF SAMEPLACE.

DEVULCANIZING-BATH.

SPECIFIUATION forming part of Letters Patent No. 665,968, dated January15, 1901.

Application filed October 18, 1900- Serial No. 33,422. (No specimens.)

To all whom it may concern.-

Be it known that 1, JOHN MURPHY, a citizen of the United States,residing in the city of New York, borough of Brooklyn, county of Kings,State of New York, have invented a new and Improved Devulcanizing-Bath,of which the following is a specification.

The object of the present invention is to produce a devulcanizing-bathfor caoutchouc, india-rubber, and similar materials; and it consists ina bath containing a desulfurizing and a deoxidizing agent, which bathmay be employed as a devulcanizing-bath for vulcanized india-rubber,&c., and when so used the desulfurizing agent acts upon the sulfur inthe vulcanized rubber to effect devulcanization and the deoxidizingagent acts upon the portions of the rubber which have become oxidized inorder to abstract oxygen therefrom.

The following are examples of baths embodying my invention: To fivepounds of vulcanized rubber I employ one pound of a solution ofcarbonate of soda and two ounces of gallic acid. The vulcanized rubberis treated in this bath for twenty hours at a temperature of 320Fahrenheit. This bath is effective to effect devulcanization of therubber by acting upon the sulfur contained therein and proportions ofthe rubber which are oxidized.

In lieu of the bath and procedure mentioned the following may beemployed accord ing to my invention:

First. Sulfid of sodium, one pound; rubher, four pounds; gallic acid,two ounces.

Second. Phosphate of soda, one pound; rubber, four pounds; gallic acid,two ounces.

Third. Carbonate of soda, one and one-half pounds; rubber, five pounds;pyrogallic acid, two ounces.

Fourth. Carbonate of soda, one and onehalf pounds; rubber, five pounds;eikonogen, two ounces.

Fifth. Carbonate of soda, one and one-half pounds; rubber, five pounds;hydrochinon, two ounces.

The quantities above mentioned may of course be increased.

Having described myinvention, what I claim, and desire to secure byLetters Patent, is-

l. The bath for devulcanizing caoutchouc, india-rubber, &c., consistingof adesnlfuriz ing agent capableof acting upon the combined sulfur ofthe mass and a separate deoxidizing agent.

2. The bath fordevulcanizing caoutchouc, india-rubber,'&c., consistingof carbonate of soda and gallic acid.

JOHN MURPHY.

Witnesses:

GEO. E. MoRsE, OTTO v. SCHRENK.

